For me personally, and for the kids I teach, I promote them to snap or whip their elbow more. The more they whip the elbow, the more the wrist and fingers will follow in sequence. So the harder you whip the elbow, the more speed/spin you will create on the pitch (any pitch, not just the drop).
2 things we can never get enough of from students: Elbow whip and push from the rubber.
When throwing the rise, what do you tell them about the elbow whip?